xref: /freebsd/sys/sys/rangeset.h (revision 42249ef2)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2019 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
8  * under sponsorship from the FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $FreeBSD$
32  */
33 
34 #ifndef	_SYS_RANGESET_H
35 #define	_SYS_RANGESET_H
36 
37 #ifdef	_KERNEL
38 
39 #include <sys/_rangeset.h>
40 
41 typedef bool (*rs_pred_t)(void *ctx, void *r);
42 
43 /*
44  * This structure must be embedded at the start of the rangeset element.
45  */
46 struct rs_el {
47 	uint64_t	re_start;	/* pctrie key */
48 	uint64_t	re_end;
49 };
50 
51 void	rangeset_init(struct rangeset *rs, rs_dup_data_t dup_data,
52 	    rs_free_data_t free_data, void *rs_data_ctx, u_int alloc_flags);
53 void	rangeset_fini(struct rangeset *rs);
54 
55 bool	rangeset_check_empty(struct rangeset *rs, uint64_t start,
56 	    uint64_t end);
57 
58 /*
59  * r point to the app data with struct rs_el at the beginning.
60  */
61 int	rangeset_insert(struct rangeset *rs, uint64_t start, uint64_t end,
62 	    void *r);
63 
64 /*
65  * Guarantees that on error the rangeset is not modified.  Remove
66  * might need to split element if its start/end completely cover the
67  * removed range, in which case ENOMEM might be returned.
68  */
69 void	rangeset_remove_all(struct rangeset *rs);
70 int	rangeset_remove(struct rangeset *rs, uint64_t start, uint64_t end);
71 int	rangeset_remove_pred(struct rangeset *rs, uint64_t start,
72 	    uint64_t end, rs_pred_t pred);
73 
74 /*
75  * Really returns the pointer to the data with struct rs_el embedded
76  * at the beginning.
77  */
78 void	*rangeset_lookup(struct rangeset *rs, uint64_t place);
79 
80 /*
81  * Copies src_rs entries into dst_rs.  dst_rs must be empty.
82  * Leaves dst_rs empty on failure.
83  */
84 int	rangeset_copy(struct rangeset *dst_rs, struct rangeset *src_rs);
85 
86 #endif
87 
88 #endif
89